Where This Guide Comes From
Every step in this article comes from one source video — Mike Builds’ full walkthrough DIY Solar Power Cart Build! 5000 Watt, 48 Volts, which has been watched more than 186,000 times. In it, he bolts a 48V server-rack battery and a 5,000W inverter onto a Harbor Freight hand truck, wires up a self-contained load center, and ends up with a portable power station that cost him about $1,860. If you would rather watch the build before reading the breakdown, the video is right here:
What This Build Packs In
The whole idea behind this cart is simplicity. Instead of spreading components across a wall or a rack in a garage, everything bolts onto one hand truck that rolls into a closet, lays flat when you need it out of the way, and shows up wherever you need power. Mike calls it a full system, and for once that phrase is accurate: inverter, battery, distribution and solar input are all mounted together, wired together, and ready to run.
The four main components are the same parts you would use in any small off-grid setup. The inverter is a SunGold 48V 5,000W single-phase unit that outputs 120V AC and takes 48V DC from the battery. It also carries a built-in MPPT solar charge controller rated up to 500V of panel input and a built-in AC charger, so one box handles solar, grid charging and inversion. The battery is a Vatrer 100Ah 48V server-rack LiFePO4 pack, and the power is distributed through an all-in-one load center with four outlets and a built-in power meter. Everything sits on a Harbor Freight hand truck with pneumatic tires.
None of these are the most expensive components money can buy, and that is deliberate. Mike’s point through the video is that a mid-range component list, assembled carefully, gives you a system that will be reliable for years and is still available when you lose power in an emergency. Cheap-of-the-cheapest parts save money once and cost you twice; these are parts he can recommend without hesitation for both full-time use and emergency backup.
The Inverter and Battery: The Two Heavy Lifters
The SunGold inverter is the brain of the cart. It takes 48V battery power and produces 120V single-phase, which covers the vast majority of tools, appliances and electronics in North America. The integrated MPPT controller accepts up to 500V of solar input and up to 5,500W of panels, which means you can wire a serious array directly into the cart without a separate charge controller. On cloudy days, the built-in AC charger steps in: plug the cart into the grid or a generator and it recharges the battery through the same unit.
Everything is programmable from the little display on the front. You set your battery charge and discharge parameters, your minimum and maximum solar charging, your minimum and maximum AC charging, and the rest of the operating envelope. SunGold has been making inverters for a long time, and plenty of other builders have run these units hard with good luck, so reliability is a reasonable expectation rather than a hope.
The Vatrer 100Ah 48V battery is the other half of the pair. It is a lithium iron phosphate pack, so the chemistry is about as safe as batteries get, and it is budget-friendly for a server-rack battery. What sets it apart is the screen: it monitors cell voltages, power in and power out, and everything else you would normally need an external shunt for, built right into the battery. It also ships with a breaker, which removes the need for a separate fuse between the battery and inverter, and it has Bluetooth, so you can keep an eye on it from your phone.
The Load Center and the Hand Truck
Getting power from the inverter to your appliances is handled by an all-in-one load center: a small distribution box with one main input breaker, four individual 20A breakers for four outlets, and a power meter on the front. This is the component Mike was most curious about before the build — he had never used one — and it turned out to be the easiest part of the whole job. Instead of buying breakers and a breaker box separately and wiring everything by hand, the unit arrives self-contained, even water-resistant, and shows you the exact watts and kilowatt-hours you are pulling.
The cart itself is a Harbor Freight hand truck dolly, roughly $60–$70. The pneumatic tires roll smoothly over gravel and grass, the battery rides on the bottom with the inverter hung above it, and the whole assembly is compact enough to store in a closet or lay flat in a vehicle. The carrying handles on the battery fold out of the way, and the ratchet strap that secures the 100 lb pack to the dolly is simple but strong enough for real use.
Wiring It Right: Gauges, Lugs and Heat Shrink
Wiring is where most DIY solar projects either work forever or fail slowly, and Mike is explicit about sizing. For the AC output from inverter to load center, 10 AWG wire works for demonstration but is undersized if you plan to max the system out; he recommends 6 AWG. The rule he gives is the one that matters: take your maximum wattage and divide by the voltage. For 5,000W at 120V that is about 41A, and you size your wire for that number, plus a safety margin for continuous loads. 10 AWG handles roughly 30A continuously, so you can see why it is borderline here.
Between the battery and the inverter, the inverter is capable of pulling over 100A from the battery, so the DC cables need to be heavy. Mike uses 2 AWG pure copper cable — specifically oxygen-free cable from Windy Nation — and makes his own lengths because the pre-made ones were too short. He explicitly warns against copper-clad aluminum wiring, which asks for trouble when connections corrode, and he uses copper lugs with marine-grade heat shrink. The heat shrink carries a glue sealant inside that creates a watertight connection, which matters even indoors because you never want moisture creeping into a terminal joint.
Pre-Charging and the DC Hookup
Before connecting the battery cables, Mike pre-charges the inverter’s capacitors to avoid a spark on the final connection. He turns the battery on and the inverter off, clips a 5W 47-ohm resistor between the positive battery cable and the positive battery terminal, and lets it sit for a minute or two. When the resistor comes off and the cable is connected, there is no spark. It is a small ritual that protects both you and the electronics, and it costs nothing.
The battery cables then land on the terminals with attention to polarity — positive to positive, negative to negative — and the terminal safety covers go back on. Because the battery has its own breaker, no separate fuse is required between battery and inverter. You can absolutely add a fuse or a disconnect for extra safety, but if you do, make sure the components are rated for the current and the connections are torque-secured; loose connections are the number one cause of heat in this kind of system.
AC, Solar and the Distribution Box
On the AC side, Mike makes a short pigtail from a 12 AWG extension cord for the inverter’s AC input, labeled L for live, N for neutral and G for ground. The same labeling applies on the output. Every inverter is a little different, so reading the manual for your exact model is non-negotiable, but the pattern is the same: line, neutral and ground in; line, neutral and ground out.
The PV input is simpler still — a positive and a negative, using 10 AWG solar wire terminated with MC4 connectors. The solar side of this build reads about 250V from the panels, so the 500V-rated MPPT controller has plenty of headroom. Inside the distribution box, the black wire is live, the white is neutral and the green is ground, each landing on a clearly labeled terminal. Mike adds ferrule ends to the stranded wires before inserting them into the inverter terminals, which keeps individual strands from poking out and creating a short inside the connection block, and he double-checks every connection in the box before closing it.
Putting the Cart to Work
The real proof of the cart is what it powers. In the video, a 12V battery charger plugged into the load center shows the inverter running at 144W — the distribution panel reads 151W with 1.4A, which matches. Charging the cart from a generator puts 21A back into the battery, and the inverter is capable of up to 40A of AC charging if you feed it from a circuit rated for more than 15A. On a cloudy, rainy day the solar side still made about 1,000W and 18A into the batteries from a 1.5kW array, at 250V.
The headline demo is a mini-split air conditioner. The cart ran it at 727W, blowing cold air, and a fully charged battery would run a 700–1,000W mini-split for roughly 5 hours. With more solar than load, it runs indefinitely; at night, 5 hours of AC from a cart you can roll into a bedroom is a genuinely useful amount of power. And because the battery has parallel-ready studs, adding a second server-rack battery is a jumper-cable job that doubles the capacity to 10.24kWh.
What It Costs — and When DIY Beats Buying
Here is the full budget from the video: the power distribution box runs about $80, the hand truck dolly about $70, the inverter anywhere from $700 to $800 (call it $750), the Vatrer 100Ah battery $860, and wiring and miscellaneous parts about $100. The grand total lands at about $1,860.
That is the honest comparison point. A comparable branded portable power station costs less up front than it did two years ago, but the components you can buy and assemble yourself are getting better and cheaper at the same time. Mike’s build took less than a day to record and could be assembled in under an hour by someone with everything laid out. What you trade is your own time, a few tools, and responsibility for the wiring — what you gain is a system you understand completely and can repair with off-the-shelf parts.
If you are comfortable crimping lugs and checking polarity, a DIY cart like this is a real value. If you would rather not own the assembly risk, a factory-built portable power station — or a factory-built battery at your voltage and capacity — is the safer route, and that is exactly what we make at Dajiu Energy when customers need a specific pack without doing the build themselves. The same thinking runs through our other buying guides: match the tool to your skill level, then size the system to the load.
And if you are not hunting for a consumer brand but need the battery itself — a custom LiFePO4 pack at a specific voltage and capacity, an OEM or ODM project, or wholesale supply for your own portable power line — that is what we do. Dajiu Energy is a Chinese manufacturer building LiFePO4 batteries for RVs, homes, golf carts and portable applications since 2017. Our product range covers LiFePO4 drop-in replacement batteries, EV and golf cart batteries, wall-mounted home storage, portable power stations, commercial energy storage and battery swap cabinets — explore the full lineup in our product center, or browse more buying guides. Tell us your voltage, capacity and size, and we’ll engineer the pack to hit it.
What Viewers Are Asking (Top Comments on the Video)
These are the most useful of the video’s top comments, with our practical answers. Where the creator replied, we quote his response; where he did not, we give our own answer written the way we would answer a customer on the shop floor. Thanks-only comments were left out on purpose; these are the ones with actual information in them.
Source video: Mike Builds — "DIY Solar Power Cart Build! 5000 watt, 48 Volts, Portable, Powerful, Easy To Build!" (youtube.com/watch?v=DPZwzdZo8eo). Comment excerpts are quoted verbatim from the video’s top comments; creator replies are marked as Mike’s reply. Build figures and the budget breakdown are transcribed from the video.